package cn.tedu.v6;

import java.io.*;
import java.net.BindException;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.*;
/**
 *Version 6 在线用户列表
 */
public class Server {
    private ServerSocket serverSocket;
    private static final Integer PORT =4567;
    private List<PrintWriter> allOut=new ArrayList<>();
    //1.私有化集合保存所有的用户名--onlineUsers
    private Map<String,String> userDataBase;

    public Server() {
        try {
            serverSocket = new ServerSocket(PORT);
            userDataBase=new HashMap<>();
            userDataBase.put("欣欣","123456");
            userDataBase.put("雨雨","654321");
        } catch (BindException e) {
            System.out.println("端口号重复申请，建议换个端口号");
        } catch (IOException e) {
            System.out.println("申请端口号失败....");
        }
    }


    public void start() {
        try {
            while (true) {
                System.out.println("-----等待客户端连接-----");
                Socket socket = serverSocket.accept();
                new Thread(new ClientHandler(socket)).start();
            }
        } catch (IOException e) {
            System.out.println("服务器端通讯断开了");
        } finally {
            if (serverSocket != null && !serverSocket.isClosed()) {
                try {
                    serverSocket.close();
                } catch (IOException e) {
                    System.out.println("服务器关闭失败");
                }
            }
        }
    }

    public static void main(String[] args) {
        new Server().start();
    }

    private synchronized void broadcastMessage(String message){
        for (PrintWriter pw:allOut){
            pw.println("消息广播："+message);
        }
    }
    //2.封装方法：同步转发给所有客户端消息：“在线用户：”+onlineUsers
    //updateOnlineUsers 更新在线人数名单的方法：“在线用户：”+onlineUsers
    //字符串： String userList=“在线用户”+String.join("、",onlineUsers)

    private class ClientHandler implements Runnable {
        private Socket socket;
        private String ip;
        private BufferedReader br;
        private PrintWriter pw;
        private String username;
        private String password;

        public ClientHandler(Socket s) {
            this.socket = s;
            ip = socket.getInetAddress().getHostAddress();

            try {
                br = new BufferedReader(new InputStreamReader(socket.getInputStream(), "UTF8"));
                pw = new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket.getOutputStream(), "UTF8")), true);
                synchronized (allOut) {
                    allOut.add(pw);
                }
            } catch (IOException e) {
                System.out.println("客户端断开通讯~~");
            }
        }

        private boolean Login(String user, String pass) {
            return userDataBase.containsKey(user) && userDataBase.get(user).equals(pass);
        }

        private void handlerChat(){
            new Thread(() -> {
                try {
                    String message;
                    while ((message = br.readLine()) != null) {
                        System.out.println(ip + "客户端说：" + message);
                        System.out.println("客户端说：请输入消息(输入 exit 退出)：");
                        System.out.println("服务器端请输入：");
                        broadcastMessage(message);
                    }
                } catch (IOException e) {
                    System.out.println("客户端读入失败!");
                }
            }).start();
            Scanner input = new Scanner(System.in);
            while (true) {
                String say = input.nextLine();
                pw.println(say);
            }
        }

        public void run() {
            try {
                pw.println("请输入用户名：");
                username = br.readLine();
                pw.println("请输入密码：");
                password = br.readLine();
                if (Login(username, password)) {
                    pw.println("登录成功，欢迎进入聊天室~");
                    //3.所有用户添加至集合中【同步】
                    handlerChat();
                } else {
                    pw.println("登录失败，用户名或者密码错误！");
                    socket.close();
                }
            } catch (NullPointerException e) {
                System.out.println("IO流传入对象，有对象为null！立马核对，建议：查看try块中对象可能赋值为null");
            } catch (IOException e) {
                System.out.println("服务器端断开链接");
            } finally {
                //4.客户端断开链接，移除当前集合【同步】
                synchronized (allOut) {
                    allOut.remove(pw);
                }
                if (br != null)
                    try {
                        br.close();
                    } catch (Exception e) {
                        System.out.println("结束通讯，关闭失败");
                    }
                if (pw != null) pw.close();
                if (socket != null && !socket.isClosed())
                    try {
                        socket.close();
                    } catch (IOException e) {
                        System.out.println("通讯关闭失败~");
                    }
                }
            }
        }
    }


